Defensive publication

ABSTRACT

BIAXIALLY ORIENTED POLYESTER FILM HAVING A PATTERN EMBOSSED ON ONE SURFACE THEREOF IS PRODUCED BY EXTRUDING THE FILM, ORIENTING THE FILM BY STRETCHING AT LEAST 2.5 TIMES IN TWO MUTUALLY PERPENDICULAR DIRECTIONS IN THE PLANE OF THE FILM, EMBOSSING ONE SURFACE OF THE FILM PRIOR TO COMPLETION OF HEAT SETTING, AND HEAT SETTING THE BIAXIALLY ORIENTED FILM. THE FILM IS EMBOSSED BY CONTACTING THE SURFACE OF THE FILM AFTER BIAXIAL ORIENTATION AND PRIOR TO COMPLETION OF HEAT SETTING WITH A METAL ROLL HAVING A SURFACE ROUGHNESS OF ABOUT FROM 25 TO 80 MICROINCHES, A.A., A TEMPERATURE OF ABOUT FROM 175* TO 220*C., AND A PRESSURE OF ABOUT FROM 40 TO 80 LBS. PER LINEAL INCH. THE METAL ROLL ALONG WITH A RUBBER ROLL FORMS A NIP THROUGH WHICH THE FILM IS PASSED TO EFFECT THE EMBOSSMENT.

DEFENSIVE PUBLICATION UNITED STATES PATENT OFFICE Published at therequest of the applicant or owner in accordance with the Notice of Dec.16, 1969, 869 O.G. 687. The abstracts of Defensive Publicationapplications are identified by distinctly numbered series and arearranged chronologically. The bending of each abstract indicates thenumber or pages of specification, including claims and sheets ofdrawings contained in the application as originally filed. The files ofthese applications are available to the public for inspection andreproduction may be purchased for 30 cents a sheet.

Defensive Publication applications have not been examined as to themerits of alleged invention. The Patent Oflice makes no assertion as tothe novelty of the disclosed subject matter.

PUBLISHED OCTOBER 1, 1974 T927,010 PROCESS FOR EMBOSSING BIAXIALLYORIENTED POLYESTER FILM Harold B. Whitfield and David J. Chalmers,Circleville,

Ohio, assignors to E. I. du Pont de Nemours and Company, Wilmington,Del.

Continuation of application Ser. No. 222,331, Jan. 31, 1972. Thisapplication Nov. 20, 1973, Ser. No. 417,594 Int. Cl. B29c 17/00 US. Cl.264-210 R No Drawing. 9 Pages Specification Biaxially oriented polyesterfilm having a pattern embossed on one surface thereof is produced byextruding the film, orienting the film by stretching at least 2.5 timesin two mutually perpendicular directions in the plane of the film,embossing one surface of the film prior to completion of heat setting,and heat setting the biaxially oriented film. The film is embossed bycontacting the surface of the film after biaxial orientation and priorto completion of heat setting with a metal roll having a surfaceroughness of about from 25 to 80 microinches, A.A., a temperature ofabout from 175 to 220 C., and a pressure of about from 40 to 80 lbs. perlineal inch. The metal roll along with a rubber roll forms a nip throughwhich the film is passed to effect the cmbossment.

